1. Field of the Invention
The present invention relates to an integrated, full coverage antenna module and, more particularly, to using an end-fire array capable of scan mounted on a top and/or a bottom surface of back-to-back side antenna arrays to form an integrated full coverage antenna module.
2. Description of the Related Art
It is desirable to have an antenna which provides 360.degree. azimuth coverage. Such full coverage is particularly desirable for airborne radar. Radar applications desiring a full coverage antenna are numerous, including airborne early warning (AEW), navigation, weather mapping, et al.
Currently, AWACs provide full coverage by physically rotating an antenna around 360.degree.. This configuration has the obvious problems of weight and mechanical requirements, as well as a fixed radar update rate.
An alternative to the rotating antenna is a dorsal fin array. The dorsal fin array is thin, light and requires no moving parts. This array consists of two conventional, electronically scanned antenna (ESA) arrays positioned back-to-back. Each of the ESA arrays usually can scan .+-.60.degree. for a combined total of 240.degree., short of the desired 360.degree.. Placing an array on either end of the back-to-back configuration, due to size constraints, won't allow these end arrays to provide nearly as much directive gain as the side-looking arrays, hence limiting the radar detection range.
Another solution consists of creating a triad array by joining three planar ESA arrays in a triangle. While providing full coverage with no mechanical parts, this configuration greatly increases the size and weight requirements of the device.